With the continuous development of distributed photovoltaic solar power market, the government gradually decreased subsidies for PV grid-connected system in many countries. More and more residential PV systems choose to use energy storage system instead of selling power to country to keep proceeds from their PV investment. There is no doubt that solar energy plus storage will become an important development direction of PV solar industry, by solving the problems of intermittent and power interruption at night. The iPower PV energy storage system developed by Dowell can be well applied for existing off/on-grid systems, and available for both large power stations and home distributed systems. Here you can find a perfect solution for the newly built energy storage system and the existing grid-connected PV systems.
In the event of power grid outage during daytime, PV system is still available because iPower is able to simulate power grid to keep the inverter working. In addition, iPower give priority to use energy from PV as back up to keep important load continuously working. If energy from PV is insufficient, then use the battery to discharge power.
This wiring is more convenient to realize for existing grid-tied PV system. We need only add iPower+batter to the system and separate important loads in a independent channel as backup loads. However, in the event of power grid outage during daytime, PV system doesn’t work any more. The battery will start to discharge energy immediately as back up to important loads.
iPower can be also used in off-grid PV system to store solar energy during daytime and discharge energy in the evening. iPower will start the diesel generator automatically if PV energy supply is insufficient. By combining off-grid PV system and generator, customer can reduce electricity cost and get rid of loud noise from diesel generator.
iPower also supports Time-of-Use management, which controls the battery to store solar energy or grid power when electricity price is low (off-peak rates) and discharge power when electricity price is high (peak rates). The UPS function allows homeowners to store solar energy from PV or power from grid and use it during electric outages.
A) Operate under off-grid state, use 6.4kWh battery, system can run lasts for 1~2 days, ensure safety without influence on life.
B) Operate under off-grid state, can use energy generated by PV, system can run for a long time with good condition of light, ensure basic electric needs without influence.
C) Operate under on-grid state, can take use of time-of-use electricity price function and adopt general operating mode, system not only can keep running without outages, but also can save electricity cost.